<Border
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Width="300"
    Background="Black"
    BorderBrush="White"
    BorderThickness="2"
    CornerRadius="5">
        <StackPanel Orientation="Vertical">
            <Label Foreground="White" FontSize="16" Content="{Binding Message}" HorizontalAlignment="Center" />
            <StackPanel Visibility="{Binding IsHighScore}" Orientation="Horizontal">
                <Label 
                    FontSize="12" 
                    Foreground="White"
                    Content="Enter your name:" 
                    Margin="5" />
                <TextBox 
                    Text="{Binding Name, Mode=TwoWay}" 
                    Width="150" 
                    MaxLength="20" 
                    Margin="5" />
            </StackPanel>
            <Button 
                FontSize="12" 
                Content="OK" 
                Command="{Binding OKCommand}" 
                HorizontalAlignment="Center"
                Margin="5"
                Width="50" />
    </StackPanel>
</Border>